yeah my guess would be that because with autogenerated IDs off, you could customize your ID to anything you want so there doesn't need to be an "alternate name" for the customer. so with it turned on, altname is used to identify just the customer name and entityID to be the number generated

our partner says when they invoked "entityid" their form returned null. weird. but as long as they end up with the correct string i'm okay with it.